International Online Survey on the Management of Patent Ductus Arteriosus.

INTRODUCTION: There is uncertainty and lack of consensus regarding optimal management of patent ductus arteriosus (PDA). We aimed to determine current clinical practice in PDA management across a range of different regions internationally. MATERIALS AND METHODS: We surveyed PDA management practices in neonatal intensive care units using a pre-piloted web-based survey, which was distributed to perinatal societies in 31 countries. The survey was available online from March 2018 to March 2019. RESULTS: There were 812 responses. The majority of clinicians (54%) did not have institutional protocols for PDA treatment, and 42% reported variable management within their own unit. Among infants <28 weeks (or <1,000 g), most clinicians (60%) treat symptomatically. Respondents in Australasia were more likely to treat PDA pre-symptomatically (44% vs. 18% all countries [OR 4.1; 95% CI 2.6-6.5; p < 0.001]), and respondents from North America were more likely to treat symptomatic PDA (67% vs. 60% all countries [OR 2.0; 95% CI 1.5-2.6; p < 0.001]). In infants ≥28 weeks (or ≥1,000 g), most clinicians (54%) treat symptomatically. Respondents in North America were more likely to treat PDAs in this group of infants conservatively (47% vs. 38% all countries [OR 2.3; 95% CI 1.7-3.2; p < 0.001]), and respondents from Asia were more likely to treat the PDA pre-symptomatically (21% vs. 7% all countries [OR 5.5; 95% CI 3.2-9.8; p < 0.001]). DISCUSSION/CONCLUSION: There were marked international differences in clinical practice, highlighting ongoing uncertainty and a lack of consensus regarding PDA management. An international conglomeration to coordinate research that prioritises and addresses these areas of contention is indicated.

The Effect of Continuous Positive Airway Pressure on Cerebral and Splanchnic Oxygenation in Preterm Infants.

BACKGROUND: Despite the known clinical benefits of continuous positive airway pressure (CPAP) to support preterm infants breathing, there are limited studies that have examined its effect on regional oxygenation. OBJECTIVES: This study aimed to investigate how the application of CPAP affects cerebral and splanchnic tissue oxygenation in preterm infants. METHODS: A pilot observational study was conducted in infants using near-infrared spectroscopy while off CPAP and on CPAP. Regional cerebral and splanchnic saturations and variability (coefficient of variability; CV) were evaluated. RESULTS: Twenty-six infants (25-37 weeks gestational age at birth) were studied. The mean cerebral oxygenation did not differ with the application of CPAP (80 ± 4.2% without CPAP; 80 ± 1.9% with CPAP), but variability around the mean was less with CPAP (CV 5 vs. 2%, respectively). Mean cerebral fractional oxygen extraction (FOE) increased with CPAP from 0.13 ± 0.06 to 0.17 ± 0.04% (p = 0.002). Splanchnic oxygenation increased significantly from 66 ± 11.6 to 75 ± 9.1% with CPAP (p < 0.001) and also became more stable (CV 13 vs. 7%, respectively). Splanchnic FOE decreased with CPAP from 0.28 ± 0.13 to 0.22 ± 0.10% (p = 0.002). CONCLUSION: The application of CPAP did not affect mean cerebral oxygenation in this group of preterm and term infants; however, it led to a significant increase in splanchnic oxygenation. These findings highlight the important role that respiratory support may play in maintaining adequate and stable oxygen delivery to vital organs.

[Nonlinear partial least squares method for simultaneous derivative spectrophotometric determination of two components in compound sulfamethoxazole].

A nonlinear model of consistency with derivative absorption in multiple components systems has been given. Model data were estimated by partial least squares method. A method for the simultaneous derivative spectrophotometric determination of two components with nonlinear partial least squares method was established. The method has been applied to the simultaneous determination of two components in compound sulfamethoxazole tablets. The average recoveries of sulfamethoxazole and trimethoprim in synthetic samples were 99.8% and 100.1%, and relative standard deviations were 1.3% and 1.6%, respectively. The results by nonlinear PLS method are significantly better than those by linear PLS method. The results for actual compound formulation agreed with those obtained by standard method.